Lamp locking lampholder for tubular lamps



Dec. 22, 1953 J. M. PISTEY LAMP LOCKING LAMPHOLDER FOR TUBULAR LAMPS Filed Nov. 5, 1952 Hi5 Ato Patented Dec. 22, 1953 LAMP LOCKIN G LAMPHOLDER FOR TUBULAR LAMPS John M. Pistey, Fairfield, Conn., assignor to General Electric Company, a corporation of New York Application November 5, 1952, Serial No. 318,850

The present invention relates to lampholders for tubular lamps of the single contact pin type and especially to the lampholder which holds the low voltage end of the lamp.

The object of the invention is to provide in a lampholder for a single contact pin type lamp an improved locking and releasing means for the contact pin which is simple in structure, reliable in use, and capable of being provided at low cost; and which is so arranged that the lamp end can be readily inserted and locked in position in the lampholder and released and removed from the lampholder by the use of only one hand, a thing of importance in connection with the use of such lampholders.

My invention relates particularly to lampholders of this type which comprise a pair of spring contact arms fixed in the lampholder housing at their inner ends, the lamp end contact pin being held between the free outer ends of the spring contact arms. According to my invention, I provide at the outer end of the lampholder housing at one side of the slot through which the contact pin is inserted into the lampholder, a pivoted locking finger made of insulating material, the inner end of which is in engagement with the inner side of one of the spring contact arms and is held by the spring contact arm over the contact pin to lock the pin in position in the lampholder, the outer end of the locking finger projecting beyond the end of the lampholder casing, the arrangement being such that turning the locking finger moves the spring contact arm to release the contact pin and permit the lamp end to drop out of or be easily moved out of the lampholder'into'the hand of the person removing the lamp.

In the drawing,

Fig. 1 is a side view showing a tubular lamp mounted at its left-hand end in a high voltage lampholder and at the other end in a low voltage lampholder embodying my invention.

Fig. 2 is a sectional view taken on line 2-2, Fig. 1.

Fig. 3 is a sectional view taken on line 3-3, Fig. 2.

Fig. 4 is a bottom planned view of the lampholder.

Fig. 5 is a detailed view illustrating the manner of releasing the lampholder locking means and removing a lamp end using only one hand.

Referring to the drawing, I indicates a tubular lamp having the contact pin 2 at its one end mounted in a lampholder 3 and the contact pin 4 at its other end mounted in a. lampholder 5 embodying my invention.

1 Claim. (01. 339-50) Lampholder 3 may be of any suitable construction. It is shown as comprising a housing 6 provided with a spring contact arm 1 with which contact pin 2 engages, the pin being inserted through an opening in the inner side wall of the housing.

Lampholder 5 comprises a housing having an inner side wall 8, an outer side wall 9, a top wall I0 and end walls II and I2. At its lower end are walls which define a terminal chamber I 3. Attached at their lower ends in terminal chamber I3 is a pair of contact arms I4 and I5 which extend up through the housing to a position adjacent the under side of top wall I0; and in top wall It] and inner side wall 8 is a slot I6 through which a contact pin on a tubular lamp end may be inserted to a position between the ends of the two contact arms. On the inner surface of wall 8 adjacent the lower end of slot I6 is a projection 11, the opposite sides of which form stops to limit movement of the contact arms toward each other and which, along with the bottom end of slot I6, forms a curve seat for a contact pin. Contact arms I4 and I5 are formed from spring strip material and contact arm I4 is constructed and arranged to be biased toward contact arm I5. They are shown as being fixed in the terminal chamber by screws I8 and as being provided with terminal screws I9. Contact arm I5 is provided with a seat 20 for a contact pin. The contact arms are forced under tension against projection I! by lugs or wings 2| formed integral with contact arms I4 and I5, the outer ends of which engage the inner surfaces of walls II and I2.

Pivotally mounted on a pivot pin 22 which extends across a slot 23 in top wall II) at the side of slot I6 adjacent contact arm I4 is a curved locking and releasing finger 24. The inner end of finger 24 projects to a position on the inner side of spring arm I4 and it is engaged by the spring arm and biased by it to a position where its inner end extends part way across slot I6. This position of the locking finger and spring arm I4 is shown in dotted lines in Fig. 2, the position being fixed by the back surface of the looking finger engaging the inner end of slot 23 which forms a stop for it. As shown in Fig. 2, the front surface of locking pin 24 is curved as indicated at 25.

To insert a lamp in a pair of holders 3 and 5 as shown in Fig. 1, one lamp end contact pin is inserted through the opening in housing 8 of lampholder 3 into engagement with contact arm I after which the contact pin at the other end of the lamp is pushed into lampholder 5 through end back into slot is in a position over the pin 7 as shown in full lines in Fig. 2, the movement being limited by arm 14 engaging the contactjpin."

This serves to lock the contact pin in the lamp:

holder.

To remove a lamp from theflampholder, the"- locking finger is engaged by a'finger of theha'nd' after the manner indicated in Fig. 5 and turned y 4 1 position. By this means my invention may be embodied in a lampholder by merely the provision of the pivoted locking finger, a thing which can be done at low cost; and since the locking finger is formed from a suitable insulating material, no exposedlive part results.

What I claim as new g andde'sire to secure by Letters Patent of the Unitedstates' is:

, In a lampholder, a housing having a slot at one end through which a contact pin on the end of a tubular lampmay be inserted, a pair of contact arms-in the housing having spaced free ends to bring its inner end out of slot 16. The'l'amp end will then drop out of or may be then moved out of the lampholder by use of the thumb as indicated in Fig. 5 and 'at the same time the lamp 'graspedby the hand and pulled free of lampholder 3; This isa simple operation and is especially advantageous where the lampholders arecei'ling mounted and faced downwardly. To be able to remove a lamp from the holderby the use of only one hand is an important safety factor for the lamp replacerl At the same time finger 24 serves to lock the lamp end in the lamp holder so it cannot accidentally fall out, a thing which may occur when lamps are ceiling mounted and the ceiling is subject to vibration. v

A feature of myinvention resides in the use of one of the spring'contact arms of the lampholderfor biasing the locking finger to locking adjacent and in alignment with said slot and shaped to define a seat for holding a tubular lamp contact pin; one of said arms being biased toward the other arm and'having an end which projects beyondsaid'seat, and a locking finger pivotally mounted at the edge of said slot having an inner end'which projects into the slot and into engagement with the inner side of said projecting contact end'an'd is'bia's'ed'by suchcontact' end to a position where it projects' partially across the slot, thebut'er end of said finger*projecting-beyond the lampholder housing to provide an actuatirig end for turning the finger; v

JOHN MJPISTEY.

References Citedin the file' of this patent UNITED sTATEs PATENTS Number I Name v I Date 2,254,222 Hubbell et al. -Sept. 2, 1941 2,289,172 Beal July 7, 1942 2,569,662 Fallek 0st. 2, 1951 

